I'm thinking of extending the house 4m out from the rear wall. We bought the house a few years ago and there was what seemed like a pretty solid patio about 4 inches below the floor level of the house. We then decked over it. If I build an extension do I need to remove the whole patio and sub base or can I just remove the part of the patio where the foundations will go? Apart from saving lots of time not having to dig it up are there other benefits of having a patio already laid where the extension will be? Could I just damp proof it/insulate it and lay a concrete slab over it?
Thx
Rich
Thx
Rich